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characterp

characterp

type: predicate function (subr)
location: built-in
source file: xlbfun.c
Common LISP compatible: yes
supported on: all machines

SYNTAX

(characterp <expr> )
        <expr>          -       the expression to check

DESCRIPTION

The CHARACTERP predicate checks if an <expr> is a character. T is returned if <expr> is a character, NIL is returned otherwise.

EXAMPLES

(characterp #\a)                        ; returns T - character
(setq a #\b)                            ; 
(characterp a)                          ; returns T - evaluates to char
(characterp "a")                        ; returns NIL - string
(characterp '(a b c))                   ; returns NIL - list
(characterp 1)                          ; returns NIL - integer
(characterp 1.2)                        ; returns NIL - float
(characterp 'a)                         ; returns NIL - symbol
(characterp #(0 1 2))                   ; returns NIL - array 
(characterp NIL)                        ; returns NIL - NIL


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